II-153
WSM Minor Change II Service Engineering Section
(5)Compressor control
When the compressor is on, the idling speed is raised by 150 rpm.
The idea is as follows.
If the compressor is repeatedly turned on and off kept off for 3 seconds, the idling speed gets back to its
original rpm. In this way, the AI motor can be kept from getting activated many times.
(Reason: If the compressor is on and the alternator barely generates power, the battery, if connected to
an external load, may fall to work.)
<Function chart>
<Function diagram>
Watching the voltage condition of compressor magnet switch, CPU in the controller commands the AI
motor to regulate the engine idle speed.
If the magnet switch is ON, then CPU commands to output 150 rpm higher than the preset idle speed.
If the magnet switch is OFF, then CPU commands to output the preset idle RPM.
Actual output from the controller is PWM current to the AI motor.
Air conditioner
Compressor
Idle RPM
ON
Idle + 150 rpm
3sec
150 rpm
AI controll
Engine speed
Idle rpm
OFF
OFF OFF
ON
OFF
ON
3sec
Input signal
Comprssor
magnet switch
-18 °C
(Program control)
30 °C
(Y=X+150)
Governor
sensor
CPU
12 V
Y
X
Controller unit
Temp.
AI motor
Engine
Comprssor
Relay
To Next Page
Loading...
Need help?
General
